So I made this.
It was a belt. Now it's my first real strap. I own another leather strap that I bought off eBay, but it's cheap and too light for anything other than a warmup.
It's 18 inches long and 1.5 inches wide. The leather was a bit stiff, so I soaked in in neatsfoot oil. Now it's soft and very supple.
Oh and if you were wondering...
...that is a Jesus fish. A friend gave it to me years ago. It was a nice gesture, but I'm not a Christian. At least this way I'll finally get some use out of it.
Now I just need to try it out.